Structural element of reinforced concrete

ABSTRACT

A heating cable is embedded in a reinforced concrete slab in serpentine formation, adjacent loops of the cable having bent over portions at opposite edge portions of the slab. Mounting supports are embedded in the slab and hold the cable in the loop formation, and guide members are affixed to respective ones of the mounting supports at the opposite edge portions for guiding the bent-over loop portions and for tensioning the heating conductor.

United States Patent [191 Krieger 1 51 Feb. 5, 1974 STRUCTURAL ELEMENTOF REINFORCED CONCRETE [76] Inventor: Heinrich Krieger, am Bembaum 57,Primary L Albrmon wlesbaden'sonnenberg Germany Attorney, Agent, orFirm-Kurt Kelman [22] Filed: Oct. 28, 1971 [2!] Appl. No.: 193,281

[57] ABSTRACT [30] Foreign Application Priority Data I Nov. 5, 1970Germany 7040944 A heating cable is embedded in a reinforced concreteAug. 4, 1971 Germany 2138961 slab in serpentine formation, adjacentloops of the Apr. 27, 1971 Germany 7116248 cable having bent overportions at opposite edge portions of the slab. Mounting supports areembedded in [52] US. Cl. 219/213, 219/345 the slab and hold the cable inthe loop formation, and [51] Int. Cl. H05b 1/00 guide members areaffixed to respective ones of the 58] Field of Search .L 219/213, 345mounting supports at the opposite edge portions for guiding thebent-over loop portions and for tensioning [56] References Cited theheating conductor.

UNITED STATES PATENTS 2,997,568 8/1961 Leipold et al 219/213 5 Claims, 6Drawing Figures 1 i \/I////Z 3,069,522 12/1962 Jamison .f. ..2l9/2l3X I1 STRUCTURAL ELEMENT OF REINFORCED CONCRETE The present inventionrelates to structural elements of reinforced concrete, and moreparticularly to ceiling plates containing electrical heating conductors.

In ceiling plates of this type, electrical heating cables have beenmanually clamped to the plates and had to be protected by a specialconcrete layer to avoid damage to the cables in subsequent buildingoperations. This is an exceedingly time-consuming procedure requiringconsiderable labor. It also subjects the cables to possible damage atthe building site.

It is the primary object of this invention to avoid the abovedisadvantages and to provide structural elements which may be mounted ina minimum of time while keeping the heating conductors protected fromweather or adverse working conditions while maintaining them in placeaccording to plan and without in any way being limited to specificheating capacities.

The above and other objects are accomplished in accordance with theinvention with mounting supports for a plurality of electrical heatingconductors. The mounting supports extend at least partially into, andengage, the concrete of the structural element, and the heatingconductors are at least partially covered by the concrete.

With this arrangement, the heating conductors are affixed to themounting supports at the time of installation and the mounting supportswith the heating conductors are then pressed into, or embedded in, theconcrete of the structural element before it is set so that the mountingsupports will be fixed on the structural element when the concrete hasset and the heating conductors will be completely or partially coveredby the concrete which thus protects the same. The mounting supports maybe concrete bars, net-like or comb-like structures, or carrier rods.

The above and other objects, advantages and features of the presentinvention will become more apparent from the following detaileddescription of now preferred embodiments thereof, taken in conjuctionwith the accompanying drawing wherein FIGS. 1 and 2 are top views ofportions of ceiling slabs with two modifications of heating conductorarrangements;

FIG. 3 is a cross section of a portion of a ceiling slab in the regionof a mounting support carrier rod for the heating conductors;

FIG. 4 is a similar cross section in the region of guide members for theheating conductors;

FIG. 5 is a section along line XIVXIV of FIG. 4; and

FIG. 6 is a cross section similar to that of FIG. 3 and showing anothermodification with guide rollers for the heating conductor.

Referring now to the drawing and first to FIGS. 1 and 2, a concreteceiling slab l is shown to have anchored in the concrete, latticegirders 3, such reinforced concrete slabs being entirely conventional.Electrical heating conductor cables 4 are embedded in the concrete.

The heating conductor 4 is carried by carrier rods 17 extending parallelto the lattice girders 3 while the major length of the heating conductorextend perpendicularly to the lattice girders. In the slab 1 of FIG. 2,

the positions of the heating conductor and carrier rods are reversed,i.e., the major length of the heating conductor extends parallel to thelattice girders while the mounting support rods 17 are perpendicular tothe girders 3.

FIG. 3 illustrates aportion of ceiling slab l to show the details of themounting. As shown, the carrier rods 17a for the heating conductor 4have a series of notches 20 dimensioned to accommodate the conductor.The lattice girder 3 has two lower chords 19 connected to the upperchord by diagonally extending braces 18, as is conventional, and thecarrier rods 17a are affixed to the girder braces in the lower regionthereof so that the chords carrying the heating conductors are embeddedin the concrete when the lattice girders are anchored thereinto. Toavoid upward movement of the heating conductors out of the notches 20during installation in the concrete, a matching rod with like notchesmay be placed over rod 17a to hold the conductors between the two rods.

As shown in FIGS. 4 and 5, the ends 17b of the carrier rods near theedges of the slab 1 have bores 21 to receive the heating conductorcables 4 and pass them perpendicularly through the carrier rod ends,after which they are guided at right angles to run along the edge of theslab, as illustrated in FIGS. 1 and 2. For purposes of guidance, guidemembers 22 are attached to the carrier rod ends 17b and project towardsthe slab edge, the guide members having arcuate guide channels or boresto maintain a minimum bending radius for the heating conductor. As shownat 23, it is possible to mount at least some of the guide membersresiliently. In the illustrated embodiment, a guide member is attachedto the carrier rod by means of a helical spring 23 surrounding theheating conductor which is being guided through the arcuate guidechannel in the guide member.

FIG. 6 shows a modification wherein the guide members 22 are replaced byguide rollers 24 whose stub axles 25 are received in respective bores inthe carrier rods 17c for heating conductors 4.

I claim:

1. A slab of reinforced concrete having opposite edges, comprising aflexible heating conductor embedded in the slab, the heating conductorbeing formed in a plurality of loops and adjacent ones of the loopshaving bent-over portions at said opposite edges, concrete reinforcingmeans at the opposite edges, mounting supports affixed to thereinforcing means, embedded in the slab and holding the heatingconductor in said loop for mation, and guidemembers affixed torespective ones of the mounting supports at said opposite edges forguiding the bent-over loop portions and for tensioning the heatingconductor.

2. The slab of claim 1, wherein said guide members are guide rollers.

3. The slab of claim 1, wherein the mounting supports are carrier barsof elastic material.

4. The slab of claim 1, further comprising spring means interposedbetween the mounting supports and the guide members for resilientlyaffixing the guide members thereto.

5. The slab of claim 1 wherein the mounting supports are carrier rodsfor the heating conductor.

1. A slab of reinforced concrete having opposite edges, comprising aflexible heating conductor embedded in the slab, the heating conductorbeing formed in a plurality of loops and adjacent ones of the loopshaving bent-over portions at said opposite edges, concrete reinforcingmeans at the opposite edges, mounting supports affixed to thereinforcing means, embedded in the slab and holding the heatingconductor in said loop formation, and guidemembers affixed to respectiveones of the mounting supports at said opposite edges for guiding thebentover loop portions and for tensioning the heating conductor.
 2. Theslab of claim 1, wherein said guide members are guide rollers.
 3. Theslab of claim 1, wherein the mounting supports are carrier bars ofelastic material.
 4. The slab of claim 1, further comprising springmeans interposed between the mounting supports and the guide members forresiliently affixing the guide members thereto.
 5. The slab of claim 1wherein the mounting supports are carrier rods for the heatingconductor.